The air traffic controllers are protesting against sanctions imposed by Enaire against 61 controllers in Barcelona after a wildcat strike which paralysed Spanish air traffic in December 2010, affecting more than 200,000 passengers on the eve of the Christmas holiday season, according to authorities.

Usca has called on Enaire to suspend the sanctions, saying in a statement most courts have concluded that there was no "disobedience nor abandonment" of their work stations.

Tourism represents nearly 11 per cent of the Spanish economy and 12 per cent of jobs.